With the publication of volume 15 (1) Persoonia has undergone a number of changes, both in the team of managing editors and in the lay-out. Dr. C. Bas retired in March 1991 from his post at the Rijksherbarium, and turned over his editorial duties to his successor, Dr. M.E. Noordeloos, after finishing volume 14, part 4, the ‘Festschrift’ dedicated to Dr. R.A. Maas Geesteranus. Dr. Bas has been an editor of Persoonia since 1972, and the present editors wish to thank him most sincerely for his efforts to maintain and improve the standard of our journal.